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Analyzing the Photo-oxidation of 2-propanol at Indoor Air Level Concentrations Using Field Asymmetric Ion Mobility Spectrometry
Published on: June 14, 2018
Primary atmospheric oxidation mechanism for toluene
Cristian O Baltaretu1, Eben I Lichtman, Amelia B Hadler
1Department of Chemistry and Biochemistry, Oberlin College, Oberlin, Ohio 44074, USA.
The Journal of Physical Chemistry. A
|January 3, 2009
Summary
A new toluene oxidation pathway producing dienedial was discovered. This finding impacts atmospheric models by clarifying the origins of glyoxal and methylglyoxal, crucial for ozone and aerosol research.
Area of Science:
- Atmospheric Chemistry
- Organic Chemistry
- Environmental Science
Background:
- Toluene is a common atmospheric pollutant.
- Understanding toluene oxidation is vital for air quality modeling.
- Previous studies identified glyoxal and methylglyoxal as key products.
Purpose of the Study:
- To investigate the primary oxidation products of toluene initiated by hydroxyl radicals (OH).
- To elucidate the reaction pathways and temperature-dependent kinetics of toluene oxidation.
- To assess the implications of new findings on atmospheric chemistry models.
Main Methods:
- Utilized turbulent flow chemical ionization mass spectrometry (TFCIMS).
- Conducted experiments across a temperature range of 228 K to 298 K.
- Analyzed reaction products to identify primary and secondary oxidation pathways.
Main Results:
- Identified a significant dienedial-producing pathway in toluene oxidation for the first time.
- Determined glyoxal and methylglyoxal to be minor primary oxidation products.
- Proposed that secondary oxidation of dienedial and epoxides explains prior observations of glyoxal and methylglyoxal.
Conclusions:
- The newly identified dienedial pathway is a null cycle for tropospheric ozone production.
- Dienedial and epoxide intermediates are crucial for understanding secondary organic aerosol formation.
- These findings necessitate revisions in atmospheric models for toluene oxidation and its impact on air quality.
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